Smartphone repurposing for open-source medical applications : HealthyPi 5 open-source multi-parameter monitor: smartphone integration and validation

Details

Supervisors

Bol, David ; Herman, Benoît

Faculty

Ecole polytechnique de Louvain

Degree label

Master [120] : ingénieur civil électricien, à finalité spécialisée

Abstract

enAccess to medical devices remains a critical challenge in low or middle income countries, where supply chain disruptions, high costs, and regulatory barriers limit the availability of essential diagnostic equipment. Open-source approaches have been proposed as a possibility to address these issues, but their practical viability remains insufficiently demonstrated. This thesis investigates to what extent smartphone repurposing can serve as a viable platform for more equitable healthcare access, across three objectives: cost reduction, supply chain resilience, and adaptation to local needs. Two complementary approaches are explored. First, a literature review of existing smartphone-based medical applications demonstrates that clinically relevant diagnostic performance can be achieved for parameters such as heart rate, SpO₂, jaundice and Parkinson's disease screening, using mostly sensors already embedded in the device. Second, the HealthyPi 5 open-source multi-parameter monitor is selected as a case study for smartphone integration. After identifying and resolving critical bugs in the firmware, ECG, respiration and PPG acquisition are brought to a functional state. A design space exploration of possible smartphone integration approaches leads to the implementation of USB and UART communication channels, enabling a cost reduction of approximately 30%. Experimental validation carried out at the Cliniques Universitaires Saint-Luc confirms the functional acquisition of ECG, respiration and heart rate, while SpO₂ estimation remains unreliable and requires further investigation. The results highlight both the promise and the current limitations of open-source medical platforms: cost reduction is achievable, firmware adaptability enables customisation that commercial devices do not allow, but supply chain resilience is not improved for platforms relying on specialised integrated circuits, and the path to clinical certification and its associated cost remain uncertain.